An Active Phased Array Receiver Based on Local Oscillator Phase Shifter

A 16-channel active phased array receiver using local oscillator (LO) phase-shifting technique is proposed in this paper for Ku-band satellite communication. Based on the combination of digital frequency synthesis (DDS) and phaselocked loop (PLL), high phase resolution (less than 1°) can be achieved. Detailed design and measured results of the proposed receiver system are provided in this paper. The measured results indicate that the system exhibits excellent spectral characteristics within the desired IF band, with a single-channel gain exceeding 40 dB. The high precision phase-shifting, low circuit complexity, and low cost all contribute to its promising prospects in the field of satellite communications.